1. Field of the Invention
This invention concerns viscometers, in general, and more specifically relates to an adapter for use with a sensitive type of viscometer.
2. Description of the Prior Art
In connection with petroleum reservior studies, it has been found that there is a need for being able to measure the viscosity of low viscosity solutions, at shear rates that are to be expected in actual reservoirs. Such shear rates are on the order of less than ten reciprocal seconds, and the low viscosity of interest is on the order of less than ten centipoise.
Heretofore, the only known instrument, or type of instrument, available for making satisfactory measurements in the indicated range of viscosity has been a Weissenburg Rheogoniometer. However, such an instrument is extremely costly and is hard to operate. On the other hand, there is an inexpensive viscometer that is commercially available and manufactured by Brookfield Engineering Laboratories, Inc. of Stoughton, Mass. 02072. The latter, however, is incapable of making accurate measurements in the low shear rate range desired. Furthermore, no known prior patent, e.g. U.S. Pat. No. 2,096,222 to G. E. Bock, Oct. 19, 1937, nor the commercial structure suggested by Brookfield in connection with its model LV Synchro-Lectric Viscometers have suggested structure for an adapter that has the desired capabilities.
Consequently, it is an object of this invention to teach a novel and mertiorous structure for an adapter that can be used with a commercial viscometer in order to provide for making accurate low shear rate measurements of fluids having low viscosity. Such adapter providing capability of accurate measurements comparable to those of a complicated Rheogoniometer.